Ingredients
For the Buckle:
2 cups cake flour
1 tsp baking powder
1/2 tsp salt
4 tbsp butter room temperature
3/4 cup sugar
1 egg
1/2 cup whole milk
1 tsp vanilla extract
3 cups fresh or frozen blueberries
For the Streusel Topping:
1/2 cup sugar
1/3 cup cake flour
1/2 tsp cinnamon
4 tbsp cold butter cubed
Instructions
Preheat oven to 375°F and grease a 9×9 baking dish.
In a bowl, whisk the flour, baking powder, and salt.
In another bowl, beat the butter and sugar until fluffy. Beat in the egg and vanilla.
Alternately mix in the flour mixture and milk, blending just until combined.
Fold in the blueberries gently.
Spread the batter evenly into the prepared pan.
Make the streusel by mixing the sugar, flour, cinnamon, and cubed butter until crumbly. Sprinkle over the batter.
Bake for 35-40 minutes until a toothpick inserted in the center comes out clean.
Allow to cool at least 10 minutes before serving warm or at room temperature.